Physical vapor deposition machine

Abstract

According to the physical vapor deposition machine table, a radio frequency coil is located between the inner side of a process cavity and a process suite, so that the sealing structure of the process cavity is simple, and the problem of electromagnetic interference is thoroughly solved. According to the technical suite, the first suite of the single-layer Faraday cage structure is adopted on the inner side, the shielding effect of the Faraday cage structure on an electromagnetic field generated by the radio frequency coil is effectively reduced, and the transmission efficiency of the electromagnetic field is improved. And the second sleeve piece made of the insulating material is additionally arranged on the outer side of the single-layer Faraday cage structure, so that sputtering ions can be effectively prevented from penetrating through a gap of the Faraday cage structure, and the damage to the interiors of the radio frequency coil and the process cavity is avoided. The process suite is relatively simple in structure, easy to disassemble for maintenance and adjustment and convenient to install. The radio frequency coil is fixed in the process cavity and located on the outer side of the second sleeve piece, the radio frequency coil is protected by the second sleeve piece and prevented from being corroded, and the radio frequency coil is detachable and convenient to maintain and adjust.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing, and in particular to a physical vapor deposition machine. Background Art

[0002] Physical vapor deposition (PVD) is a key technology for thin film deposition in the field of semiconductor manufacturing. This technology uses argon ions excited by a power source to bombard the surface of the target material to achieve physical deposition. Compared with other chemical deposition or atomic deposition, physical deposition has advantages such as faster deposition speed, denser thin film materials and lower cost, and is widely used in semiconductor manufacturing. However, compared with chemical deposition or atomic deposition, physical sputtering has the disadvantage of poor hole filling ability, mainly because the sputtered particles scatter in a cosine manner, and the sputtering rates at different positions of the target are also different, which makes it easy for the physical sputtering machine to overhang during filling, and finally shows the problem of poor step coverage. With the development of semiconductor manufacturing processes, the minimum feature size (also called critical dimension or CD size) required to fill holes has higher and higher aspect ratio requirements, and it is becoming more and more difficult to fill holes. Physical sputtering technology needs to be continuously optimized and improved to meet the needs of advanced process development. Among them, how to generate and control plasma to achieve uniformity is the key to achieving good performance of PVD type equipment.

[0003] Usually, PVD equipment uses capacitively coupled plasma (CCP). The target and wafer form two natural electrodes. Electrons are accelerated in the electric field formed by the two opposing electrodes to generate plasma. The plasma generated by CCP has good uniformity, but the ionization rate is low, which is not conducive to control and regulation. Inductively coupled plasma (ICP) is different from CCP. ICP generates an induced magnetic field by passing an alternating current through a coil. The induced magnetic field generates an induced electric field. Electrons are accelerated in the induced electric field to generate plasma. The ionization rate is high and it is widely used in the etching field. However, the uniformity of the plasma is poor and complex electromagnetic design is required. How to make full use of the advantages of the two different plasma technologies of CCP / ICP in PVD equipment, and then achieve good equipment performance by generating and controlling good plasma, is the current direction of exploration and improvement in the industry. Summary of the invention

[0004] The present application provides a physical vapor deposition machine with a simple sealing structure and solves the problem of electromagnetic interference.

[0005] In the first aspect, the present application provides a physical vapor deposition machine that may include: a process chamber, a process kit and a radio frequency coil. Among them, the process kit is fixed inside the process chamber, and the process kit includes a first kit and a second kit. The first kit is a conductive material and has a Faraday cage structure, and the second kit is an insulating material and is arranged around the first kit. The radio frequency coil is a metal coil such as a copper coil. The radio frequency coil is fixed inside the process chamber, and the radio frequency coil is arranged around the outside of the second kit. In the physical vapor deposition machine, the target material is generally placed at the top of the process chamber, and the base for carrying the wafer is generally placed at the bottom of the process chamber. The radio frequency coil is generally arranged in a position parallel to the top of the base so as to form an electromagnetic field above the base to achieve a high ionization rate of plasma.

[0006] In the present application, the process chamber is an integrated chamber, and the RF coil is located between the inner side of the process chamber and the process kit, so that the sealing structure of the process chamber is simple, and the problem of electromagnetic interference is completely solved. The process kit adopts a first kit with a single-layer Faraday cage structure on the inner side, which effectively reduces the shielding effect of the Faraday cage structure on the electromagnetic field generated by the RF coil and improves the transmission efficiency of the electromagnetic field. At the same time, the process kit adds a second kit of insulating material on the outer side of the single-layer Faraday cage structure. The second kit can be an integrated structure. The second kit replaces the existing outer Faraday cage structure, which can effectively prevent sputtering ions from passing through the gap of the Faraday cage structure, causing damage to the RF coil and the inside of the process chamber. The structure of the process kit is relatively simple, easy to disassemble for maintenance and adjustment, and convenient to install. The RF coil can be made of metal material, the RF coil is fixed inside the process chamber and located outside the second kit, the RF coil is insulated and protected by the second kit to avoid corrosion, and the second kit does not seal the RF coil, so the RF coil is detachable, which is convenient for maintenance and adjustment. Under normal circumstances, the first kit and the second kit can be routinely replaced and cleaned with the maintenance cycle, and the RF coil can be decided whether to replace and clean regularly according to actual conditions.

[0007] In some embodiments of the present application, the first kit may further include a flange fixed to the bottom of the Faraday cage structure, a portion of the structure of the flange is located on the inner side of the Faraday cage structure, and another portion of the structure of the flange is located on the outer side of the Faraday cage structure, and the flange is in a double flange shape. Since the side wall of the Faraday cage structure of the first kit is perforated to form a slit, some sputtered ions may be ejected toward the second kit, and the double flange-shaped flange at the bottom can accommodate the fallen particles. Specifically, the flange can be divided into three parts: a flange plate, an inner flange sleeve, and an outer flange sleeve, and these three parts are integrally formed. The plane where the flange plate is located is roughly perpendicular to the extension direction of the side wall of the Faraday cage structure, and the flange plate is divided into an inner ring plate and an outer ring plate by the side wall of the Faraday cage structure, and the inner ring plate is located on the inner side of the Faraday cage structure, and the outer ring plate is located on the outer side of the Faraday cage structure. The inner flange sleeve is located at the inner edge of the flange plate, and there is a spacing between the inner flange sleeve and the inner arm of the Faraday cage structure. The inner flange sleeve, the inner ring plate and the inner wall of the Faraday cage structure form a first annular groove structure, which can accommodate particles falling from the side wall of the Faraday cage structure during sputtering. The outer flange sleeve is located at the outer edge of the flange plate, and there is a spacing between the outer flange sleeve and the outer arm of the Faraday cage structure. The outer flange sleeve, the outer ring plate and the outer wall of the Faraday cage structure form a second annular groove structure, which can accommodate particles falling from the second set during sputtering.

[0008] In some embodiments of the present application, in the vertical direction, the height of the inner flange sleeve may be greater than the height of the outer flange sleeve, so that the depth of the first annular groove structure is greater than the depth of the second annular groove structure, so as to accommodate more fallen particles.

[0009] In some embodiments of the present application, the second set generally has the same central axis as the first set, that is, the second set and the first set can be coaxially arranged. In order to allow particles falling from the second set to fall into the second annular groove structure as much as possible, the second set can be located above the outer flange sleeve, and a distance must be left between the second set and the outer flange sleeve to ensure that the ion gas has good uniform flow therebetween.

[0010] In some embodiments of the present application, the inner diameter of the second set may be the same as the inner diameter of the outer flange sleeve to facilitate installation.

[0011] In some embodiments of the present application, the process kit may further include a connecting ring located at the top of the process kit, and the connecting ring may be directly fixed to the top of the process chamber, or the connecting ring may be fixed to the inner side wall of the process chamber near the top. The connecting ring may be specifically connected to the chamber adapter, and may be fixed and heat-dissipated by the chamber adapter. The top of the first kit and the top of the second kit may both be fixed to the connecting ring, and specifically, flange structures may be provided at the top of the first kit and the top of the second kit, respectively, and this may be achieved by fixing the flange structure to the connecting ring.

[0012] In some embodiments of the present application, the material of the second set may be an insulating material such as ceramic or quartz. The outer side wall of the second set may have a stepped structure, that is, the thickness of the side wall of the second set may change in a step-like manner, and this structural design is relatively simple. The stepped structure may specifically include a first step portion and a second step portion. In the horizontal direction, the thickness of the first step portion is greater than the thickness of the second step portion. The first step portion is located above the second step portion, and the top of the first step portion may be fixed to the connecting ring by a flange structure. In the horizontal direction, the second step portion is located between the radio frequency coil and the Faraday cage structure. In the vertical direction, the height of the second step portion is approximately equal to or slightly greater than the height of the radio frequency coil.

[0013] In some other embodiments of the present application, the outer side wall of the second kit may also be a smooth structure, in which case the process kit may further include a third kit. To meet the heat dissipation requirements, the third kit may be made of a conductive material, and the third kit is arranged in contact with the outer side wall of the second kit. In order to leave room for the RF coil, the third kit may be located above the RF coil, and the height of the third kit needs to be less than the height of the second kit. The top of the third kit may be fixed to the connecting ring by a flange structure.

[0014] In an embodiment of the present application, the Faraday cage structure of the first set has a plurality of slits that penetrate the thickness of the side wall, that is, in the horizontal direction, each slit will penetrate the side wall of the Faraday cage, and the electromagnetic field generated by the radio frequency coil can be transmitted through the plurality of slits. In order to achieve better radio frequency magnetic field penetration efficiency, the present application optimizes the distribution of the slits, and the distribution of the slits can be adjusted according to the process requirements. The principle of slit adjustment is: at the relative position of the radio frequency coil, which can also be considered to be close to the position of the wafer placed on the base for the deposition process, that is, the position where the electromagnetic field needs to be generated above the wafer, the distribution density of the slits is appropriately increased; at the top of the Faraday cage structure close to the target material and the bottom of the Faraday cage structure close to the bottom of the process chamber, that is, the position where the electromagnetic field does not need to be generated, the distribution density of the slits is reduced or no slits are set. Specifically, the distribution density of the slits can be increased or decreased by adjusting the slit shape, slit size and slit distribution position.

[0015] In some embodiments of the present application, the Faraday cage structure may specifically include a plurality of longitudinal slits, and the distribution density of the slits may be adjusted by adjusting the slit width of the longitudinal slits. Specifically, the top of the longitudinal slit is cut off at a certain distance from the target material, that is, no slit is provided at a position close to the target material, and the bottom of the longitudinal slit is cut off at a certain distance from the bottom of the process chamber, that is, no slit is provided at the bottom of the process chamber. From the top of the process chamber to the bottom, that is, in the vertical direction, the slit width of the plurality of longitudinal slits gradually increases, that is, at the position where the electromagnetic field needs to be generated above the wafer, the slit width of the longitudinal slit is the largest.

[0016] In other embodiments of the present application, each longitudinal slit of the Faraday cage structure may be connected to a plurality of transverse slits. The slit width of a longitudinal slit is uniformly set, and the distribution density of the slits can be controlled by adjusting the distribution position of the transverse slits connected to the longitudinal slit. Specifically, the number of the plurality of transverse slits is the largest at the set position of the RF coil, that is, relatively dense transverse slits are concentrated at the position where the electromagnetic field needs to be generated above the wafer. In addition, the plurality of transverse slits connected to adjacent longitudinal slits may be distributed in an aligned manner, or may be staggered.

[0017] In some embodiments of the present application, a plurality of insulating fixing brackets can be installed on the inner wall of the process chamber, and the insulating fixing brackets can be made of ceramic material. The second set and can be directly located on the insulating fixing bracket. Each insulating fixing bracket has at least one through hole for passing the radio frequency coil, and the radio frequency coil can be fixed in position through the through hole of the insulating fixing bracket. The insulating fixing bracket can be fixed to the inner wall of the process chamber by screws, and the screws can specifically be insulating screws such as ceramic materials. Each insulating fixing bracket can be provided with two screws, and the two screws are respectively located on the upper and lower sides of the through hole. In addition, in order to ensure that the integrated design of the process chamber can have a better electromagnetic shielding effect, the thickness of the side wall of the process chamber can be increased to reduce electromagnetic interference, so that the screws will not penetrate the side wall of the process chamber while ensuring the fixing effect.

[0018] In some embodiments of the present application, one end of the RF coil can be connected to the RF signal as an input end, and the other end of the RF coil can be directly grounded as an output end, or connected to an external signal through an RF terminal for adding a DC signal or other signal. The RF interface is connected from the outside, and the RF interface needs to pass through the side wall of the process chamber and connect to the input end of the RF coil located inside the process chamber. The outside of the RF interface can be wrapped with insulating material and pass through the side wall of the process chamber, so that one end of the RF interface is exposed outside the process chamber to access the RF signal. The other end of the RF interface can extend into the interior of the process chamber and connect to the input end of the RF coil. In addition, in order to ensure the sealing between the insulating material outside the RF interface and the through hole of the side wall of the process chamber, a flange seal can be used on the outside. The insulating material can be consistent with the material of the insulating fixing bracket, and the two can be an integral structure, or the two can be separately and independently set.

[0019] In some embodiments of the present application, the electromagnet can be separately arranged as a first electromagnet and a second electromagnet surrounding the outside of the process chamber, and the first electromagnet and the second electromagnet are respectively installed on the upper and lower sides of the RF interface so that the installation space is not limited.

[0020] In some embodiments of the present application, a magnetic field shielding protective cover can also be installed outside the process chamber, and the radio frequency interface, the first electromagnet and the second electromagnet can all be placed in the magnetic field shielding protective cover. The magnetic field shielding protective cover can be made of a material with high electrical conductivity or high magnetic permeability, and the magnetic field shielding protective cover can reduce the electromagnetic interference of the electromagnet to the outside, and can also ensure the isolation of the interference of the external electromagnetic field to the internal electromagnet and the radio frequency interface.

[0021] In other embodiments of the present application, the other end of the RF interface can be connected to the input end of the RF coil through an elastic component to ensure that when the RF coil becomes abnormal and needs to be repaired or replaced, the abnormal RF coil can be easily removed, and the replacement normal RF coil can have a good sealing connection with the other end of the RF interface through the elastic component after installation.

[0022] In the embodiment of the present application, the target can be connected to a DC power supply, the base can be connected to an AC power supply, and the RF coil can be connected to an RF power supply. In order to give full play to the advantages of the two plasma modes of CCP / ICP, the physical vapor deposition machine provided by the present application can be used to perform deposition and etching processes step by step to form a good hole filling effect.

[0023] In the first working mode, CCP capacitive coupling mode, magnetron sputtering deposition can be performed. The AC power supply loads an AC signal to the wafer placed on the base, the DC power supply loads a DC signal to the target material, and the RF power supply loads an RF signal to the RF coil. The DC signal and the RF signal are used to excite the argon plasma, bombarding the target surface to generate target plasma, which is physically deposited to the holes of the wafer. Due to the poor collimation of PVD physical deposition, the hole filling ability is weak, so an overhang phenomenon is formed on the top of the CD morphology, which affects the hole filling effect.

[0024] In the second working mode, ICP inductive coupling mode, etching can be performed. The AC power supply loads a bias voltage signal to the wafer placed on the base, the DC power supply stops loading DC power to the target, and only the RF power supply loads the RF signal to the RF coil. Since the target has no negative bias and no target bombardment, the argon plasma is used to bombard the CD morphology surface of the wafer, which can eat up the overhanging deposited material similar to dry etching, achieving better step coverage.

[0025] In the actual process, the above two working modes can be flexibly selected and combined, for example, three cycles of the first working mode are performed, and then one cycle of the second working mode is performed, so that the deposition and etching processes are alternately performed, which can form a good hole filling effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of a physical vapor deposition machine provided in an embodiment of the present application;

[0027] Figure 2 A schematic diagram of the structure of the first kit provided in an embodiment of the present application;

[0028] Figure 3a A schematic diagram of the structure of the second kit provided in an embodiment of the present application;

[0029] Figure 3b Another structural schematic diagram of the second kit provided in an embodiment of the present application;

[0030] Figure 4 A schematic diagram of a structure of a radio frequency interface connected to a radio frequency coil provided in an embodiment of the present application;

[0031] Figure 5 A schematic diagram of a top view of the physical vapor deposition machine provided in an embodiment of the present application;

[0032] Figure 6 Another structural schematic diagram of a radio frequency interface connected to a radio frequency coil provided in an embodiment of the present application;

[0033] Figure 7 A schematic diagram of the side structure of the radio frequency interface provided in an embodiment of the present application;

[0034] Figure 8 A schematic diagram of a slit structure of a Faraday cage structure provided in an embodiment of the present application;

[0035] Figure 9a A schematic diagram of another slit structure of a Faraday cage structure provided in an embodiment of the present application;

[0036] Figure 9b for Figure 9a Schematic diagram of the corresponding transverse gap structure distribution;

[0037] Fig.10 Another structural schematic diagram of a physical vapor deposition machine provided in an embodiment of the present application;

[0038] Fig.11 A schematic diagram of the hole morphology of the physical vapor deposition machine provided in an embodiment of the present application after the deposition process and the etching process.

[0039] Reference numerals:

[0040] 1-process chamber; 2-process kit; 3-RF coil; 3a-input end; 3b-output end; 21-first kit; 22-second kit; 23-connecting ring; 24-third kit; 211-Faraday cage structure; 212-flange; 2121-flange plate; 2122-inner flange sleeve; 2123-outer flange sleeve; 221-first step; 222-second step; 2111-longitudinal slit; 2112-transverse slit; 31-insulating fixing frame; 311-screw; 32-RF interface; 321-insulating material; 322-flange; 33-elastic component; 34-electromagnet; 341-first electromagnet; 342-second electromagnet; 35-magnetic field shielding protective cover; 4-target material; 5-base; 61-DC power supply; 62-AC power supply; 63-RF power supply. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below in conjunction with the accompanying drawings.

[0042] The terms used in the following embodiments are only for the purpose of describing specific embodiments and are not intended to be limiting of the present application. As used in the specification and appended claims of the present application, the singular expressions "a", "an", "said", "above", "the" and "this" are intended to also include expressions such as "one or more", unless there is a clear contrary indication in the context.

[0043] References to "one embodiment" or "some embodiments" etc. described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application. Thus, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear at different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0044] In addition, the same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted. The words expressing positions and directions described in this application are all explained with reference to the drawings as examples, but they can be changed as needed, and the changes are all included in the protection scope of this application. The drawings of this application are only used to illustrate the relative position relationship and do not represent the true proportion.

[0045] The two plasma technologies of capacitive coupling CCP and inductive coupling ICP have their own advantages and disadvantages. How to make full use of the advantages of these two different plasma technologies in PVD type equipment, and then achieve good equipment performance by generating and controlling good plasma, is the direction of exploration and improvement in the current industry. An existing CCP / ICP combination technology is to add a coil to realize the ICP function on the basis of the CCP mode. That is, a coil is added to the process kit inside the process chamber. The coil is usually made of the same material as the target material, and the coil is made into a sheet-like sub-target shape. By applying a DC power signal and a radio frequency power signal to the coil, a high ionization rate of the plasma is achieved. Since the coil is installed inside the process kit as a sub-target, additional materials will be deposited on the sub-target. After long-term operation, a particle source will be generated. At the same time, the sub-target will also be etched during operation. Therefore, in actual application, the sub-target needs to be replaced regularly. At the same time, since the sub-target and the wafer are in the same space (that is, inside the process kit), a complex structure needs to be designed during installation to ensure the installation and connection of the power path.

[0046] Another existing CCP / ICP combination technology is to add a radio frequency coil between the inside of the process chamber and the process kit on the basis of the CCP mode. The radio frequency coil is a metal coil and is installed and fixed on the inner wall of the process chamber. Although the radio frequency coil will not be easily generated by the deposited material and particles, since the process kit is usually made of metal, the electromagnetic field generated by the radio frequency coil will be shielded by the metal of the process kit, and it cannot be effectively transmitted to the inside of the process kit to realize the high-density plasma mode of ICP. Therefore, the process kit will be made into the shape of a Faraday cage to avoid the formation of ion shielding by the process kit. In addition, in order to prevent the sputtered ions from passing through the slits in the Faraday cage and damaging the inner wall of the process chamber, it is necessary to add an additional layer of process kit with a Faraday cage structure, and the two layers of process kits are staggered to realize the protection of the inner wall of the process chamber. At the same time, it is necessary to add an additional layer of ceramic shield to protect the radio frequency coil to realize the high ionization rate working mode of ICP. The process kit with a two-layer Faraday cage structure will seriously affect the penetration efficiency of the electromagnetic field generated by the RF coil. Therefore, it is necessary to increase the penetration of the electromagnetic field by adding magnetic materials to the outer Faraday cage structure. This will cause the structure of the process kit to be complex and increase the cost. At the same time, the lower electromagnetic transmission efficiency means more serious eddy current heating loss, which will affect the performance stability of the process kit. In addition, in order to ensure the installation of the RF coil, the internal structure of the process chamber will be designed into multiple sections. Its sealing structure is complex, which affects the installation space of the upper and lower electromagnets outside the process chamber. More sealing surfaces also mean that more external electromagnetic fields are easily coupled into the process chamber, generating additional electromagnetic interference. In addition, the RF coil fixedly installed on the inner wall of the process chamber needs to be enclosed by a ceramic shielding cover, which makes it impossible to quickly check, replace and adjust the RF coil during equipment maintenance.

[0047] The physical vapor deposition machine provided in the present application adopts a novel process kit structural design, which can solve the electromagnetic interference problem and has a simple structure and is easy to seal.

[0048] The physical vapor deposition machine provided in the present application is described in detail below with reference to the accompanying drawings.

[0049] Figure 1 A structural diagram of a physical vapor deposition machine provided in an embodiment of the present application is schematically shown.

[0050] Reference Figure 1In the implementation of the present application, the physical vapor deposition machine includes: a process chamber 1, a process kit 2 and a radio frequency coil 3. Among them, the process kit 2 is fixed inside the process chamber 1, and the process kit 2 includes a first kit 21 and a second kit 22. The first kit 21 is a conductive material and has a Faraday cage structure 211, and the second kit 22 is an insulating material and is arranged around the first kit 21. The radio frequency coil 3 is a metal coil such as a copper coil. The radio frequency coil 3 is fixed inside the process chamber 1, and the radio frequency coil 3 is arranged around the outside of the second kit 22. In the physical vapor deposition machine, the target material 4 is generally placed on the top of the process chamber 1, and the base 5 for carrying the wafer is generally placed at the bottom of the process chamber 1. The radio frequency coil 3 is generally arranged at a position parallel to the top of the base 5, so as to form an electromagnetic field above the base 5 to achieve a high ionization rate of plasma.

[0051] In the present application, the process chamber 1 is an integrated chamber, and the RF coil 3 is located between the inner side of the process chamber 1 and the outer side of the process kit 2, so that the sealing structure of the process chamber 1 is simple, and the problem of electromagnetic interference is completely solved. The process chamber 1 adopts a first kit 21 of a single-layer Faraday cage structure 211 on the inner side, which effectively reduces the shielding effect of the Faraday cage structure 211 on the electromagnetic field generated by the RF coil 3, and improves the transmission efficiency of the electromagnetic field. At the same time, the process kit 2 adds a second kit 22 of insulating material on the outer side of the single-layer Faraday cage structure 211. The second kit 22 can be an integrated structure. The second kit 22 replaces the existing outer Faraday cage structure, which can effectively prevent sputtering ions from passing through the gap of the Faraday cage structure 211, thereby damaging the RF coil 3 and the interior of the process chamber 1. The process kit 2 has a relatively simple structure, is easy to disassemble for maintenance and adjustment, and is also convenient to install. The RF coil 3 can be made of metal material. The RF coil 3 is fixed inside the process chamber 1 and outside the second set 22. The RF coil 3 is insulated and protected by the second set 22 to prevent corrosion. The second set 22 does not enclose the RF coil 3, so the RF coil 3 is detachable for easy maintenance and adjustment. Under normal circumstances, the Faraday cage structure 211 and the second set 22 can be routinely replaced and cleaned according to the maintenance cycle. The RF coil 3 can be replaced and cleaned regularly according to actual conditions.

[0052] In the present application, a distance needs to be left between the first set 21 and the second set 22 in the process set 2 to ensure that the ion gas has good uniform flow therebetween.

[0053] Figure 2 The structural diagram of the first kit provided in the embodiment of the present application is exemplarily shown.

[0054] Reference Figure 2In some embodiments of the present application, the first kit 21 may further include a flange 212 fixed to the bottom of the Faraday cage structure 211, a portion of the structure of the flange 212 is located inside the Faraday cage structure 211, and another portion of the structure of the flange 212 is located outside the Faraday cage structure 211, and the flange 212 may be in a double flange shape. Since the side wall of the Faraday cage structure 211 of the first kit 21 is perforated to form a slit, some sputtered ions may be ejected toward the second kit 22, and the double flange-shaped flange 212 can accommodate fallen particles. Specifically, the flange 212 can be divided into three parts: a flange plate 2121, an inner flange sleeve 2122, and an outer flange sleeve 2123, and these three parts are integrally formed or assembled separately. The plane where the flange plate 2121 is located is roughly perpendicular to the extension direction of the side wall of the Faraday cage structure 211. The flange plate 2121 is divided into an inner ring plate and an outer ring plate by the side wall of the Faraday cage structure 211. The inner ring plate is located inside the Faraday cage structure 211, and the outer ring plate is located outside the Faraday cage structure 211. The inner flange sleeve 2122 is located at the inner edge of the flange plate 2121, and there is a gap between the inner flange sleeve 2122 and the inner arm of the Faraday cage structure 211. The inner flange sleeve 2122, the inner ring plate and the inner wall of the Faraday cage structure 211 form a first annular groove structure, which can accommodate particles falling from the side wall of the Faraday cage structure 211 during sputtering. The outer flange sleeve 2123 is located at the outer edge of the flange plate 2121, and there is a distance between the outer flange sleeve 2123 and the outer arm of the Faraday cage structure 211. A second annular groove structure is formed between the outer flange sleeve 2123, the outer ring plate and the outer side wall of the Faraday cage structure 211, and the second annular groove structure can accommodate particles falling from the second kit 22 during sputtering.

[0055] Reference Figure 2 In some embodiments of the present application, in the vertical direction, the height of the inner flange sleeve 2122 may be greater than the height of the outer flange sleeve 2123, so that the depth of the first annular groove structure is greater than the depth of the second annular groove structure, so as to accommodate more fallen particles.

[0056] Figure 3a A schematic diagram of the structure of the second kit provided in an embodiment of the present application is exemplarily shown. Figure 3b Another structural schematic diagram of the second kit provided in an embodiment of the present application is exemplarily shown.

[0057] Reference Figure 3a and Figure 3bIn some embodiments of the present application, the second set 22 and the first set 21 generally have the same central axis, that is, the second set 22 and the first set 21 can be coaxially arranged. In order to allow the particles falling from the second set 22 to fall into the second annular groove structure as much as possible, the second set 22 can be located above the outer flange sleeve 2123, and a distance must be left between the second set 22 and the outer flange sleeve 2123 to ensure that the ion gas has good uniform flow therebetween.

[0058] Reference Figure 3a and Figure 3b In some embodiments of the present application, the inner diameter of the second set 22 can be the same as the inner diameter of the outer flange sleeve 2123 to facilitate installation.

[0059] Reference Figure 3a and Figure 3b In some embodiments of the present application, the process kit 2 may further include a connecting ring 23 located at the top of the process kit 2. The connecting ring 23 may be directly fixed to the top of the process chamber 1, or the connecting ring 23 may be fixed to the inner wall of the process chamber 1 near the top. The connecting ring 23 may be specifically connected to the chamber adapter, and may be fixed and heat-dissipated by the chamber adapter. The top of the first kit 21 and the top of the second kit 22 may both be fixed to the connecting ring 23, and specifically, flange structures may be provided at the top of the first kit 21 and the top of the second kit 22, respectively, and this may be achieved by fixing the flange structure to the connecting ring 23.

[0060] Reference Figure 3a In some embodiments of the present application, the material of the second set 22 may be an insulating material such as ceramic or quartz. The outer side wall of the second set 22 may have a stepped structure, that is, the thickness of the side wall of the second set 22 may change in a step-like manner, and this structural design is relatively simple. The stepped structure may specifically include a first step portion 221 and a second step portion 222. In the horizontal direction, the thickness of the first step portion 221 is greater than the thickness of the second step portion 222. The first step portion 221 is located above the second step portion 222, and the top of the first step portion 221 may be fixed to the connecting ring 23 through a flange structure. In the horizontal direction, the second step portion 222 is located between the radio frequency coil 3 and the Faraday cage structure 211. In the vertical direction, the height of the second step portion 222 is approximately equal to or slightly greater than the height of the radio frequency coil 3.

[0061] Reference Figure 3bIn some other embodiments of the present application, the outer side wall of the second set 22 may also be a smooth structure. In this case, the process set 2 may further include a third set 24. To meet the heat dissipation requirements, the third set 24 may be made of an electrically conductive and thermally conductive material, and the third set 24 is arranged in contact with the outer side wall of the second set 22. In order to leave room for the RF coil 3, the third set 24 may be located above the RF coil 3, and the height of the third set 24 needs to be less than the height of the second set 22. The top of the third set 24 may be fixed to the connecting ring 23 by a flange structure.

[0062] Figure 4 A schematic diagram of a structure of a radio frequency interface connected to a radio frequency coil provided in an embodiment of the present application is shown schematically. Figure 5 The top view of the physical vapor deposition machine provided in the embodiment of the present application is schematically shown.

[0063] Reference Figure 4 and Figure 5 In some embodiments of the present application, a plurality of insulating brackets 31 can be installed on the inner wall of the process chamber 1. The insulating brackets 31 can be made of ceramic material. The bottoms of the second set 22 and the third set 24 can also be directly located on the insulating brackets 31. Each insulating bracket 31 has at least one through hole for passing the RF coil 3. The RF coil 3 can be fixed in position through the through hole of the insulating bracket 31. Figure 4 In the description, an example is given in which three through holes are provided on each insulating fixing frame 31 .

[0064] Figure 6 Another structural diagram of a radio frequency interface connected to a radio frequency coil provided in an embodiment of the present application is schematically shown.

[0065] Reference Figure 6 The insulating fixing bracket 31 can be fixed to the inner wall of the process chamber 1 by means of screws 311, and the screws 311 can be insulating screws such as ceramic materials. Two screws 311 can be provided for each insulating fixing bracket 31, and the two screws 311 are respectively located on the upper side and the lower side of the through hole. In addition, in order to ensure that the integrated design of the process chamber 1 can have a better electromagnetic shielding effect, the side wall thickness of the process chamber 1 can be increased to reduce electromagnetic interference, and the screws 311 will not penetrate the side wall of the process chamber 1 while ensuring the fixing effect.

[0066] In the present application, one end of the RF coil 3 can be connected to the RF signal as the input end 3a, and the other end of the RF coil 3 can be directly grounded (GND) as the output end 3b, or connected to an external signal through an RF terminal for adding a DC signal or other signal. The RF interface 32 is connected from the outside, and the RF interface 32 needs to pass through the side wall of the process chamber 1 and be connected to the input end 3a of the RF coil 3 located inside the process chamber 1.

[0067] Figure 7 A schematic diagram of the side structure of the radio frequency interface provided in an embodiment of the present application is shown schematically.

[0068] Specifically, refer to Figure 4 , Figure 6 and Figure 7 , the outside of the RF interface 32 can be wrapped with an insulating material 321 and then pass through the side wall of the process chamber 1, so that one end of the RF interface 32 is exposed outside the process chamber 1 to access the RF signal. The other end of the RF interface 32 can extend into the interior of the process chamber 1 and connect to the input end 3a of the RF coil 3. In addition, in order to ensure the sealing between the insulating material 321 outside the RF interface 32 and the through hole on the side wall of the process chamber 1, a flange 322 can be used for sealing on the outside. The insulating material 321 can be consistent with the material of the insulating fixing bracket 31, and the two can be an integrated structure, or the two can be separately and independently set.

[0069] Reference Figure 4 In some embodiments of the present application, the electromagnet 34 can be separately arranged as a first electromagnet 341 and a second electromagnet 342 surrounding the outside of the process chamber 1, and the first electromagnet 341 and the second electromagnet 342 are respectively installed on the upper side and the lower side of the RF interface 32, so that the installation and adjustment space is not restricted.

[0070] Reference Figure 4 In some embodiments of the present application, a magnetic field shielding protective cover 35 can also be installed outside the process chamber 1, and the RF interface 32, the first electromagnet 341 and the second electromagnet 342 can all be placed in the magnetic field shielding protective cover 35. The magnetic field shielding protective cover 35 can be made of a material with high electrical conductivity or high magnetic permeability, and the magnetic field shielding protective cover 35 can reduce the electromagnetic interference of the electromagnet 34 to the outside, and can also ensure the isolation of the interference of the external electromagnetic field on the internal electromagnet 34 and the RF interface 32.

[0071] Reference Figure 6In some other embodiments of the present application, the other end of the RF interface 32 can be connected to the input end 3a of the RF coil 3 through an elastic component 33, so as to facilitate the removal of the abnormal RF coil 3 when the RF coil 3 is abnormal and needs to be repaired and replaced. After the replacement normal RF coil 3 is installed, it can have a good sealing connection effect with the other end of the RF interface 32 through the elastic component 33. In the embodiment of the present application, the Faraday cage structure 211 of the first kit 21 has a plurality of slits that penetrate the thickness of the side wall, that is, in the horizontal direction, each slit will penetrate the side wall of the Faraday cage 211, and the electromagnetic field generated by the RF coil 3 can be transmitted through the plurality of slits. In order to achieve better RF magnetic field penetration efficiency, the present application optimizes the distribution of slits, and the distribution of slits can be adjusted according to process requirements. The principle of slit adjustment is: at the relative position of the RF coil 3, which can also be considered to be close to the position of the wafer (wafer) placed on the base 5 for implementing the deposition process, that is, the position where the electromagnetic field needs to be generated above the wafer, the distribution density of the slits is appropriately increased; at the top of the Faraday cage structure 211 close to the target material 4 and the bottom of the Faraday cage structure 211 close to the bottom of the process chamber 1, that is, the position where the electromagnetic field does not need to be generated, the distribution density of the slits is reduced or no slits are set. Specifically, the distribution density of the slits can be increased or decreased by adjusting the slit shape, slit size and slit distribution position.

[0072] Figure 8 A schematic diagram of a slit structure of a Faraday cage structure provided in an embodiment of the present application is schematically shown.

[0073] Reference Figure 8 In some embodiments of the present application, the Faraday cage structure 211 may specifically include a plurality of longitudinal slits 2111, and the distribution density of the slits may be adjusted by adjusting the slit width of the longitudinal slits 2111. Specifically, the top of the longitudinal slit 2111 is cut off at a certain distance from the target 4, that is, no slit is provided at a position close to the target 4, and the bottom of the longitudinal slit 2111 is cut off at a certain distance from the bottom of the process chamber 1, that is, no slit is provided at the bottom of the process chamber 1. In the direction from the top of the process chamber 1 to the bottom, that is, the vertical direction, the slit width of the plurality of longitudinal slits 2111 gradually increases, that is, the slit width of the longitudinal slit 2111 is the largest at the position where the electromagnetic field needs to be generated above the wafer.

[0074] Figure 9a Another schematic diagram of the slit structure of the Faraday cage structure provided in an embodiment of the present application is schematically shown; Figure 9b Schematically shows Figure 9a Schematic diagram of the corresponding transverse gap structure distribution.

[0075] Reference Figure 9a and Figure 9bIn other embodiments of the present application, each longitudinal slit 2111 of the Faraday cage structure 211 may also be connected to a plurality of transverse slits 2112. The slit width of a longitudinal slit 2111 is uniformly set, and the distribution density of the slits can be regulated by adjusting the distribution position of the transverse slits 2112 connected to a longitudinal slit 2111. Specifically, the number of the plurality of transverse slits 2112 is the largest at the set position of the RF coil 3 (at the arrow position in the figure), that is, relatively dense transverse slits 2112 are concentrated at the position where an electromagnetic field needs to be generated above the wafer. In addition, the plurality of transverse slits 2112 connected to adjacent longitudinal slits 2111 may be distributed in an aligned manner, or may be staggered.

[0076] Fig.10 Another structural diagram of the physical vapor deposition machine provided in an embodiment of the present application is schematically shown.

[0077] Reference Fig.10 In the embodiment of the present application, the target 4 can be connected to a DC power supply 61, the base 5 can be connected to an AC power supply 62, and the RF coil 3 can be connected to an RF power supply 63. In order to give full play to the advantages of the two plasma modes of CCP / ICP, the physical vapor deposition machine provided by the present application can be used to perform deposition and etching processes step by step to form a good hole filling effect.

[0078] Fig.11 A schematic diagram schematically shows the hole morphology of the physical vapor deposition machine provided in an embodiment of the present application after the deposition process and the etching process.

[0079] In the first working mode, CCP mode, magnetron sputtering deposition (dep) can be performed. The AC power supply 62 loads an AC signal to the wafer placed on the base 5, the DC power supply 61 loads a DC signal to the target 4, and the RF power supply 63 loads an RF signal to the RF coil 3. The DC signal and the RF signal are used to excite argon plasma, bombarding the surface of the target 4 to generate target plasma, which is physically deposited to the holes of the wafer to form a deposited film layer x, referring to Fig.11 Middle upper figure. Due to the poor collimation of PVD physical deposition, the hole filling ability is weak, so the deposited film layer x forms an overhang on the top of the CD morphology, which affects the hole filling effect.

[0080] In the second working mode, that is, ICP mode, etching can be performed. The AC power supply 62 loads a bias voltage signal (bias power) to the wafer placed on the base 5, and the DC power supply 61 stops loading DC power to the target 4. Only the RF power supply 63 loads the RF signal to the RF coil 3. Since the target 4 has no negative bias voltage and there is no target 4 bombardment, the CD morphology surface of the deposited film layer x of the wafer is bombarded with argon plasma, which can eat up the overhanging deposited material similar to dry etching. Fig.11 Middle and lower picture, achieving better step coverage.

[0081] In the actual process, the above two working modes can be flexibly selected and combined, for example, three cycles of the first working mode are performed, and then one cycle of the second working mode is performed, so that the deposition and etching processes are alternately performed, which can form a good hole filling effect.

[0082] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A physical vapor deposition machine, characterized in that: include: Process chamber; A process kit is fixed inside the process chamber, the process kit includes a first kit and a second kit, the first kit is made of conductive material and has a Faraday cage structure, and the second kit is made of insulating material and is arranged around the first kit; The radio frequency coil is fixed inside the process chamber and is arranged around the outside of the second set.

2. The physical vapor deposition machine according to claim 1, characterized in that: The first kit further comprises a flange fixed to the bottom of the Faraday cage structure, wherein the flange comprises a flange plate, an inner flange sleeve and an outer flange sleeve; The flange plate is fixed to the bottom of the Faraday cage structure; The inner flange is located at the inner edge of the flange plate, and there is a distance between the inner flange sleeve and the inner arm of the Faraday cage structure; The outer flange sleeve is located at the outer edge of the flange plate, and there is a distance between the outer flange and the outer arm of the Faraday cage structure.

3. The physical vapor deposition machine according to claim 2, characterized in that: The height of the inner flange sleeve is greater than the height of the outer flange sleeve.

4. The physical vapor deposition machine according to claim 3, characterized in that: The outer flange sleeve and the inner flange sleeve have the same central axis, and the second set is located above the outer flange sleeve.

5. The physical vapor deposition machine according to claim 4, characterized in that: The inner diameter of the second sleeve is the same as the inner diameter of the outer flange sleeve.

6. The physical vapor deposition machine according to any one of claims 1 to 5, characterized in that: The process kit further comprises a connecting ring located at the top of the process kit, and the top of the first kit and the top of the second kit are both fixed to the connecting ring.

7. The physical vapor deposition machine according to claim 6, characterized in that: The outer side of the second set has a stepped structure, the stepped structure has a first stepped portion and a second stepped portion, and the thickness of the first stepped portion is greater than the thickness of the second stepped portion; The first step portion is located above the second step portion and is fixed to the connecting ring, and the second step portion is located between the radio frequency coil and the Faraday cage structure.

8. The physical vapor deposition machine according to claim 6, characterized in that: The process kit also includes a third kit, which is made of conductive material. The top of the third kit is fixed to the connecting ring, and the third kit is in contact with the outer side wall of the second kit. The height of the third kit is less than that of the second kit, and the third kit is located above the RF coil.

9. The physical vapor deposition machine according to any one of claims 1 to 8, characterized in that: The Faraday cage structure of the first set has a plurality of slits, and the distribution density of the plurality of slits is the largest at positions opposite to the radio frequency coils.

10. The physical vapor deposition apparatus according to claim 9, wherein: The Faraday cage structure comprises a plurality of longitudinal slits, which are gradually increased in width from the top to the bottom of the process chamber.

11. The physical vapor deposition machine according to claim 9, characterized in that: The Faraday cage structure includes a plurality of longitudinal slits, each of the longitudinal slits is connected to a plurality of transverse slits, and the number of the plurality of transverse slits is the largest at the setting position of the radio frequency coil.

12. The physical vapor deposition machine according to any one of claims 1 to 11, characterized in that: It also includes a plurality of insulating fixing frames fixed to the inner wall of the process chamber, and each of the insulating fixing frames has at least one through hole for penetrating the radio frequency coil.

13. The physical vapor deposition apparatus according to claim 12, wherein: It also includes a radio frequency interface, one end of which is located outside the process chamber, the other end of which passes through the process chamber and is connected to the input end of the radio frequency coil, and the output end of the radio frequency coil is grounded.

14. The physical vapor deposition apparatus according to claim 13, wherein: The other end of the radio frequency interface is connected to the input end of the radio frequency coil through an elastic component.

15. The physical vapor deposition machine according to claim 13 or 14, characterized in that: It also includes a first electromagnet and a second electromagnet surrounding the outside of the process chamber, wherein the first electromagnet and the second electromagnet are respectively disposed on the upper side and the lower side of the radio frequency interface.

16. The physical vapor deposition apparatus according to claim 15, wherein: It also includes a magnetic field shielding protective cover located outside the process chamber, and the radio frequency interface, the first electromagnet and the second electromagnet are all placed in the magnetic field shielding protective cover.

17. The physical vapor deposition machine according to any one of claims 1 to 16, characterized in that: It also includes a target material placed on the top of the process chamber, a base placed on the bottom of the process chamber, a DC power supply connected to the target material, an AC power supply connected to the base, and a radio frequency power supply connected to the radio frequency coil; In response to the first working mode, the AC power supply loads an AC signal to the wafer placed on the base, the DC power supply loads a DC signal to the target, and the RF power supply loads an RF signal to the RF coil; In response to the second working mode, the AC power supply loads a bias voltage signal to the wafer placed on the base, the DC power supply stops loading DC power to the target, and the RF power supply loads a RF signal to the RF coil.

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